trever1t

iTrader: (14)

20" tires and 4.56 gears, keeping rpms below 1900 and stripping the truck of all unecessary weight

lchauvin88

well ill start with putting the stockers back on and changing the flex tube to straight tubing cutting the front of the airbox open and see where that takes me

skyhighsami

iTrader: (8)

You need to sit down and figure out just how much an increase of 15.5 mpg will net you total economy wise. I think it would be foolish to sell your truck if it doesn't get 15.5 because you will likely lose more than the difference of economy over a 1 year time frame just in deprecation from what you bought it for. I would get a tune, intake, efans, and maybe a muffler. Also give it a tune up and let it ride, I wouldn't put the stock wheels on it because you bought it for the way it looks with the 22s and putting the stockers on it would be a step back IMO

KLUG'S SS

iTrader: (6)

Like other guys have stated already efans do help in mileage. The only way I could really maybe see 18mpg in the city would be to put it in open loop and tune your cruise afr cells for 15.5-16 AFR and even then then I am not sure.

That is asking an awful lot from a fullsize truck!!! Personally I know driving a fullsize truck especially with mods the whole gas mileage thing is pretty much out the window so I dont worry about it too much. When I say this I am not trying to be a ***** in anyway but maybe you should think about a small car if you are that worried about mileage or maybe get a second vehicle just an old beater or something. I have a 93 ford ranger with the 4 cyl. that i drive back and forth to work and it gets 25-26 mpg.

SnakeOiler

iTrader: (6)

I think you are misunderstanding some points. You probably ARE getting the 15.5mpg that you want, already. Your PCM is not tuned for the tire size you have, so you don't really know.

I'm just saying that with the truck you have, 14mpg isn't bad.

For 18mpg in city, that would be more on your driving than any type of mod you could do (other than installing an electric motor). But, what was mentioned are good mods to do. What brings down the gas mileage in town is accelerating and sitting still idling. Eliminate these factors and you will have great gas mileage

Get the proper sized tires on the truck and do some research on hypermilers - you can use some tips from these guys. I would think 17 mpg would definitely be in reach, 18mpg. . . . maybe.

lchauvin88

Not at all. I didn't buy the truck for how it looked on 22''s. I bought it because I needed a fullsize truck to seat me my girlfreind and the two kids. I also have a 94' mustang GT that I drag race. Pretty much I needed a tow truck that could seat my family and pull my car. This truck just so happened to be in my price range and fit those features.

Yes I have thought about another car, but Im also buying a house right now and unfortunately that is not within my budget right now.

As for the tune up, the plugs and wires are maybe, MAYBE, a month and a half old. The oil is royal purple syn 5w-20 (what the book reccomends) and that is the same age in months, and has maybe 1.5k miles on it. I have the k&n filter and a magnaflow 3.5'' in 2.5'' dual out the back. Those are my mods.

I have put the stockers on, and I can tell that the truck seems to accell easier, stop faster, and when the trans shifts it doesnt hit as hard.

I am going to locate some efans, a junkyard nearby has some camaros and firebirds, but I think they are v6 cars. Do those use the same fans as the ls1//lt1? Also, I found and intake on ebay thats $38 and $21 to ship so Im going to order it just for the tube.

Sorry for misunderstanding the facts. I see what you are talking about now.

fastnblu

iTrader: (2)

Mileage. The way a gas needle moves from "Full"- 1/2 way mark vs 1/2- Empty in relations to gallons in tank isn't perfect, for lack of a better way to say. For arguments sake,...it will be. So hypothetically, each 1/2 tank= 180 mi.
180 x 2= 360. The guy u got truck from said he got 375. That's a tiny difference.
IDK what u get on the low side (MPG) or high side. But your avg is 14.8. So let's say u get a low of 13.6 mpg & hi 16 mpg. U basically want a 10% improvemt.
Window sticker:@ the time OEMs rated mpg different than they do now. Today's figures are most realistic in how calculated. The old figures have been recalc'd & that info is available.

Bill, u also make 550+ to the wheels.

U needed a tow truck to fit family & pull car. Not tryin to be a dick, just reiterating what u said.
U need spaces for 4 people, a given. Equipment? = more space. Misc. stuff= more space. If I was in your shoes, I'd have a truck of some kind.

It does fit your needs, so what I'm sayin is sometimes (not always) u have to give up a little to get something else in return.

lchauvin88

Hey guys I have a rough update for you all. I squeezed 81.5miles between F and 3/4 mark. Did some highway driving and got 205.8miles to the half mark.

My avg isn't 14.8. My lowest Ive seen was 13.8ish and highest was 14.8. So that averaged I guesstimate 14.2mpg.

So anyways. When I fill back up Ill let you guys know what I got mpg.

GMCtrk

iTrader: (27)

Your highway mileage sucks. I easily get 250 miles to the half tank pure highway. On a trip back after getting my 6.0 installed I knocked down 23.5 with my 4.8L in the bed. In town I get 12-13. Granted I am 2wd, but you should be getting at least 19-20 on the highway.

lchauvin88

Sorry I should've mentioned that the first 1/4 tank was strictly city driving which is an improvement over 64 - 70 miles which is what i usually get.

The second quarter and half of the third quarter (where I ended the trip) was highway mileage.

BTW, my truck's 2wd too! I'd love to get at least 20 on hwy! I really want 18mpg in city but Ill go with 17 if a tune, efans and cai will get me that.

QUESTION: would it be a better idea to cut the front of my air box open, or cut a 3.5" hole in it and glue a piece of pvc tubing to it and make a ram air setup using the hole on the passenger side where the tow hook is? Which would benefit me the most? Ram air or open element?